The campaign in Massachusetts seeking to repeal a law barring discrimination against transgender people in public accommodations is resorting to old tactics of stoking unfounded fears about male sexual predators being allowed in women’s restrooms.

The ad is unveiled as Massachusetts voters are poised to vote in November on Question 3, which will decide whether the state will retain its non-discrimination law against anti-trans discrimination in public accommodations, including restrooms and locker rooms. The law was signed by Republican Gov. Charlie Baker in 2016 and has been on the books for two years, but placed on the ballot as a result of a voter-initiated referendum.

Although similar anti-trans ads haved stoked fears about children being molested in public restrooms, the 30-second ad made public Wednesday by the “No on 3” campaign, which has dubbed itself “Keep MA Safe,” features an adult woman entering the locker room as a sinister-looking male predator wearing a hoodie awaits inside a stall.

“What does the Question 3 mean to you?” asks female voice in the ad. “It means any man who says he is a woman can enter a woman’s locker room, dressing room or bathroom at any time, even convicted sex offenders, and if you see something suspicious and say something to authorities, you could be arrested and fined up $15,000.”

As the women is beginning to undo her clothes, the camera pans to her frightened face as the man snaps the stall open and releases a menacing, throaty gasp.

The female voice concludes: “Vote No on 3. This bathroom bill puts our privacy and safety at risk. It goes too far.”

Opponents have resorted fear-mongering over sexual predators in the restrooms and locker rooms again and again in the efforts to derail transgender non-discrimination measure.

In 2015, a similar ad aired in Houston as the city considered the Houston Equal Rights Ordinance and resulted in the votes rejected the non-discrimination measure — which would have prohibited discrimination on the basis of numerous characteristics, including race, religious, sexual orientation and gender identity — by a large margin at the ballot.

After that loss, transgender advocates started airing their own ads about the personal stories of transgender people in defense of non-discrimination laws. Earlier this year, a similar bathroom ad in Anchorage as voters in the municipality considered was repeal of a transgender non-discrimination ordinance. Despite the fear-mongering, voters decided to retain the measure on the books, marking the first time a transgender non-discrimination was upheld at the ballot.

It’s not the first time the anti-trans Massachusetts campaign has resorted to stoking fears about bathroom use, but that ad is no longer available to the public. In May, “No on 3” aired an ad the campaign was subsequently forced to edit because it was revealed to have been filmed in a Wegman’s store without the consent of the owners and over their objections. The ad has since been removed entirely.

Concerns laws against discrimination enabling sexual predators has proven unfounded based on the lack of problems in jurisdictions with such laws on the books, including 20 states and D.C.

Just last week, the Williams Institute at the University of California, Los Angeles, made public a study that found after passage of these laws, there were actually fewer incidents of privacy and safety violations than in places without gender-identity inclusive public accommodations laws.

Kasey Suffredini, co-chair for the “Yes on 3” campaign, said the new anti-trans ad “flies in the face of the indisputable facts that show women – or anyone else for that matter – are absolutely not put at risk by this law.”

“This law simply protects transgender people from discrimination in public places and that is why law enforcement leaders from across Massachusetts and the leading sexual assault prevention groups support upholding this law,” Suffredini said. “The ‘no’ campaign has no data to back up their claims, and yet is attempting to scare voters, which is truly unfortunate.”

The “Yes on 3” campaign has already made public a 2-minute video featuring transgender people in Massachusetts and their families who feel they would be subject to discrimination and physical danger if the law prohibiting anti-trans discrimination in public accommodations was repealed.

According to the “Yes on 3” campaign, the Massachusetts Chiefs of Police Association and the Massachusetts Coalition Against Sexual Assault & Domestic Violence have come out favor of the statewide protections.

Although municipalities have previously held votes on transgender non-discrimination protections, Question 3 marks the first time such a vote will be considered at the statewide law. Observers have said a loss would green light further erosion of LGBT rights, but majority support for the law at the ballot would help advance LGBT rights elsewhere.

One poll shows things are looking good for the transgender non-discrimination law. On Wednesday, a Suffolk University Political Research Center/Boston Globe poll found 73 percent voters favoring keeping the law as it is, 17 percent want the law repealed and nine percent are undecided.